508881721 has 2 divisors, whose sum is σ = 508881722. Its totient is φ = 508881720.

The previous prime is 508881719. The next prime is 508881767. The reversal of 508881721 is 127188805.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 452030121 + 56851600 = 21261^2 + 7540^2 .

It is a cyclic number.

It is not a de Polignac number, because 508881721 - 2¹ = 508881719 is a prime.

Together with 508881719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (508881701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254440860 + 254440861.

It is an arithmetic number, because the mean of its divisors is an integer number (254440861).

Almost surely, 2^508881721 is an apocalyptic number.

It is an amenable number.

508881721 is a deficient number, since it is larger than the sum of its proper divisors (1).

508881721 is an equidigital number, since it uses as much as digits as its factorization.

508881721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 35840, while the sum is 40.

The square root of 508881721 is about 22558.4068808061. The cubic root of 508881721 is about 798.3725880118.

The spelling of 508881721 in words is "five hundred eight million, eight hundred eighty-one thousand, seven hundred twenty-one".